Diagonal Rule(Different form of Fig. 5.13, p. 128) :
Diagonal Rule(Different form of Fig. 5.13, p. 128) 1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
6s 6p 6d
7s 7p To determine the electron configuration of an element, fill the orbitals in order (follow the arrows, going to the tail of the next arrow each time)
Fill each sublevel up completely before moving to the next one 2 6 10 14
Maximum capacity for sublevels
Shortcut for Writing Electron Configurations :
Shortcut for Writing Electron Configurations For the higher atomic numbers, it gets pretty lengthy to write out the entire electron configuration
To save time, write the previous noble gas symbol in brackets, then finish the electron configuration by picking up with the “s” sublevel of the next row
Example: Cl = [Ne] 3s23p5
Using the Periodic Table :
Using the Periodic Table Originally, the Periodic Table was constructed by placing elements with similar properties in the same column
Element properties are determined by the electron configuration
Therefore, the placement of elements on the PT is based on the elements’ electron configurations
Slide 5:
Li, Na, K?
Be, Mg, Ca?
B, Al, Ga?
Ne, Ar, Kr? Ti, Zr, Hf?
Cu, Ag, Au?
Zn, Cd, Hg?
Nd, U? s1 s2 p1 p6 f 4 d10 d9 d2 Elements in the same column end with the same electron configuration!
Numbering the Sublevels :
Numbering the Sublevels Column sublevel letter & exponent
Coefficient depends on sublevel:
If n = row number
Coefficient for s & p sublevels = n
Coefficient for d sublevels = n - 1
Coefficient for f sublevels = n – 2